CVE-2026-6477
Publication date 14 May 2026
Last updated 22 May 2026
Ubuntu priority
Description
Use of inherently dangerous function PQfn(..., result_is_int=0, ...) in PostgreSQL libpq lo_export(), lo_read(), lo_lseek64(), and lo_tell64() functions allows the server superuser to overwrite a client stack buffer with an arbitrarily-large response. Like gets(), PQfn(..., result_is_int=0, ...) stores arbitrary-length, server-determined data into a buffer of unspecified size. Because both the \lo_export command in psql and pg_dump call lo_read(), the server superuser can overwrite pg_dump or psql stack memory. Versions before PostgreSQL 18.4, 17.10, 16.14, 15.18, and 14.23 are affected.
Status
| Package | Ubuntu Release | Status |
|---|---|---|
| postgresql-18 | 26.04 LTS resolute |
Fixed 18.4-0ubuntu0.26.04.1
|
| 25.10 questing | Not in release | |
| 24.04 LTS noble | Not in release | |
| 22.04 LTS jammy | Not in release | |
| postgresql-17 | 26.04 LTS resolute | Not in release |
| 25.10 questing |
Fixed 17.10-0ubuntu0.25.10.1
|
|
| 24.04 LTS noble | Not in release | |
| 22.04 LTS jammy | Not in release | |
| postgresql-16 | 26.04 LTS resolute | Not in release |
| 25.10 questing | Not in release | |
| 24.04 LTS noble |
Fixed 16.14-0ubuntu0.24.04.1
|
|
| 22.04 LTS jammy | Not in release | |
| postgresql-14 | 26.04 LTS resolute | Not in release |
| 25.10 questing | Not in release | |
| 24.04 LTS noble | Not in release | |
| 22.04 LTS jammy |
Fixed 14.23-0ubuntu0.22.04.1
|
|
| postgresql-12 | 26.04 LTS resolute | Not in release |
| 25.10 questing | Not in release | |
| 24.04 LTS noble | Not in release | |
| 22.04 LTS jammy | Not in release | |
| 20.04 LTS focal |
Needs evaluation
|
|
| postgresql-10 | 26.04 LTS resolute | Not in release |
| 25.10 questing | Not in release | |
| 24.04 LTS noble | Not in release | |
| 22.04 LTS jammy | Not in release | |
| 18.04 LTS bionic |
Needs evaluation
|
|
| postgresql-9.5 | 26.04 LTS resolute | Not in release |
| 25.10 questing | Not in release | |
| 24.04 LTS noble | Not in release | |
| 22.04 LTS jammy | Not in release | |
| 16.04 LTS xenial |
Needs evaluation
|
|
| postgresql-9.3 | 26.04 LTS resolute | Not in release |
| 25.10 questing | Not in release | |
| 24.04 LTS noble | Not in release | |
| 22.04 LTS jammy | Not in release | |
| 14.04 LTS trusty |
Vulnerable, fix deferred
|
Notes
leosilva
PostgreSQL 9.3 is end of life upstream, and no updates are are available. Marking as deferred in -esm-main releases.
Severity score breakdown
| Parameter | Value |
|---|---|
| Base score |
8.8 · High
|
| Attack vector | Network |
| Attack complexity | Low |
| Privileges required | None |
| User interaction | Required |
| Scope | Unchanged |
| Confidentiality | High |
| Integrity impact | High |
| Availability impact | High |
| Vector | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H |
References
Related Ubuntu Security Notices (USN)
- USN-8294-1
- PostgreSQL vulnerabilities
- 21 May 2026